Which option orders the events chronologically, from earliest to latest.(1 point)
Responses
Many new animal species evolve. Single-celled organisms increase atmospheric methane concentrations. Photosynthesizing bacteria release oxygen into the sea. Oxygen concentrations increase in the atmosphere.
Many new animal species evolve. Single-celled organisms increase atmospheric methane concentrations. Photosynthesizing bacteria release oxygen into the sea. Oxygen concentrations increase in the atmosphere.
Single-celled organisms increase atmospheric methane concentrations. Photosynthesizing bacteria release oxygen into the sea. Oxygen concentrations increase in the atmosphere. Many new animal species evolve.
Single-celled organisms increase atmospheric methane concentrations. Photosynthesizing bacteria release oxygen into the sea. Oxygen concentrations increase in the atmosphere. Many new animal species evolve.
Single-celled organisms increase atmospheric methane concentrations. Oxygen concentrations increase in the atmosphere. Photosynthesizing bacteria release oxygen into the sea. Many new animal species evolve.
Single-celled organisms increase atmospheric methane concentrations. Oxygen concentrations increase in the atmosphere. Photosynthesizing bacteria release oxygen into the sea. Many new animal species evolve.
Photosynthesizing bacteria release oxygen into the sea. Oxygen concentrations increase in the atmosphere. Many new animal species evolve. Single-celled organisms increase atmospheric methane concentrations.
Single-celled organisms increase atmospheric methane concentrations. Photosynthesizing bacteria release oxygen into the sea. Oxygen concentrations increase in the atmosphere. Many new animal species evolve.
Animals with shells and hard parts were dominant for the first time.
increased oxygen concentration
reptiles
Earth cooled.
Which characteristic defines the Paleozoic era?(1 point)
Responses
Mammals and other warm-blooded animals became dominant.
Mammals and other warm-blooded animals became dominant.
Reptiles became dominant after a mass extinction.
Reptiles became dominant after a mass extinction.
Animals with shells and hard parts were dominant for the first time.
Animals with shells and hard parts were dominant for the first time.
Simple, one-celled life forms were dominant.
How did the success of photosynthetic bacteria change Earth’s atmosphere?(1 point)
Responses
increased oxygen concentration
increased oxygen concentration
decreased oxygen concentration
decreased oxygen concentration
decreased hydrogen concentration
decreased hydrogen concentration
increased hydrogen concentration
Which forms of life were dominant in the Mesozoic era?(1 point)
Responses
reptiles
reptiles
mammals
mammals
one-celled animals
one-celled animals
birds
How did reduced methane concentrations in the atmosphere affect Earth?(1 point)
Responses
Earth cooled.
Earth cooled.
Volcanic activity decreased.
Volcanic activity decreased.
Earth warmed.
Earth warmed.
Volcanic activity increased.